Compressor



H. E. DURGIN Oct. 30, 1962 COMPRESSOR 5 Sheets-Sheet 1 Filed Oct. 51.1960 INVENTOR. HARRY E. DONG/IV WWW V- PW.

ATTORNEY Oct. 30, 19 62 H. E. DURGIN 3,061,180

COMPRESSOR Filed Oct. 31, 1960 5 Sheets-Sheet 2 INVENTOR. HARM D 'Y I/Vff; WM

ATTORNEY H. E. DURGIN 3,061,180

Oct. 30, 1962 COMPRESSOR 5 Sheets-Sheet 3 Filed Oct. 51. 1960 INVENTOR.HARRY 5. D0 R IIV BY fim/fl PW ATTORNEY Oct. 30, 1962 Filed Oct. 31,1960 H. E. DURGIN COMPRESSOR 5 Sheets-Sheet 4 HARM 5- D WW 7W IN VENTOR.

URG/A/ ATTORNEY 5 Sheets-Sheet 5 INVENTOR.

ATTORNEY H. E. DURGIN COMPRESSOR Oct. 30, 1962 Filed Oct. 51, 1960 HARRYE. DURG/n/ BY MM Patented Oct. 30, 1962 3,061,180 COMPRESSGR Harry E.Durgin, East Hanover, NJ. (PMR Station Manager, P.0. Box 31, Naalehu,Hawaii) Filed Oct. 31, 1960, Ser. No. 66,317

Claims. (Cl. 230-444) My invention relates generally to compressors andspecifically to rotary compressors.

It is among the objects of my invention to provide a rotary compressorwhich minimizes the frictional contact of rotating vanes and the gravelubrication problems which arise therefrom.

It is yet a further object of my invention to provide a compressor whichoperates efficiently with only approximate engagement of the rotatingvanes, rather than exceedingly critical engagement of the rotatingvanes.

It is yet a further object of my invention to provide a rotarycompressor which is simple in form, easy to construct, durable, andhighly efiicient.

These objects and advantages, 'as well as other objects and advantagesmay be achieved by the device shown by way of illustration in thedrawings in which-- 7 FIGURE 1 is a view in perspective of thecompressor with portions of the housing exploded away;

FIGURE 2 is a side elevational view of the eliptical drive gears;

FIGURE 3, diagrams 1 to 16 show the complete compression cycle;

FIGURE 4 is a perspective view showing the compressor housing with thewalls partly exploded away;

FIGURE 5 is an end view of the housing showing the compressor valves andvalve drives;

FTGURE 6 is a side view of the housing showing the compressor-valvedrives;

FIGURE 7 is a top plan view of a valve passage;

FIGURE 8 is a top plan view of the valve ports in the housing;

FIGURE 9 is a side view of the valve plug;

FIGURE 10 is a front view of the valve plug;

FIGURE 11 is a horizontal sectional view of the valve plug in the valvepassage;

FIGURE 12 is a vertical sectional View of the valve plug in the valvepassage; and

FIGURE 13 is an end sectional view of the housing, valve passage andimpeller.

Referring now to the drawings in detail, my compressor has a housing 21,which is generally tubular in shape. It defines a chamber having auniform cross sectional area from end to end and having end walls 22 toenclose the ends of the chamber. The end walls each support a bearing 23and the bearings carry a shaft 24 which extends at both ends outside thechamber. The shaft is tubular and contains solid second shaft 25. Thissecond shaft is supported at its outer ends by second bearings 26. Thefirst tubular shaft 24 is provided with diametrically opposed radialslots 27. The solid second shaft is provided with a radial impeller 28.The impeller 28 is a generally rectangular member extending through theradial slots 27 in the tubular first shaft 24. The impeller extends anequal distance out from the slot on both sides of the second shaft 25.The first shaft 24 is also provided with unitary radial impellers 29which extend from the shaft in opposition to each other. The outer edgesof the four ends of the impellers 23, 28, 29, 29 all define the samecircle upon rotation. The slots 27 in the first shaft 24 divergeoutwardly so that the impellers 28 on the second shaft may approach orretreat from the impellers 29 on the first shaft 24. That is to say, theradial slots 27 in the first tubular shaft 24 are flared outwardly andare wider than the impeller 28 mounted on the second shaft 25 so thatwhen the slot is stationary, the second shaft may nevertheless be movedaround forward and backward. As a result, the space between the impeller28 on the second shaft 25 and the impellers 29 on the first shaft 24will define a space that will vary as to cubic content, dependent uponthe position of the impellers 28, 2 9 with respect to each other. Theouter edges of the impeilers 28, 29 are close to (.l") the inside of thechamher 2 1 so as to substantially seal the space on one side of theimpellers 23, 29 from the other. Also the side edges 30 of the impellers28, 29 likewise come close to (.1) the corresponding interior end wallsof the housing 21 to complete the seal.

The housing 21 is provided with alternate intake 31 and discharge 32ports disposed radially with respect to the axis of rotation of theshafts. These alternate discharge 32 ports and intake 31 ports aredisposed at an angle of from each other. The admission of gaseousmaterial into the housing through the intake 31 ports is governed by thevalves which operate in timed relation to the impellers 23, 29. Thedischarge of gaseous material from the housing 21 through the exhaustports 32 is governed by the valves 33, 34 which operate in timedrelation to the impellers 28, 29. Thus when the impellers 28,

29 subtend the intake port 31, the intake valves 33, 33 are open. Theincrease in cubic capacity of the chamber defined between the impellers28, 29 opposite the intake port 31 reduces the pressure in the saidchamber and the intake valve 33 being open, admits gaseous material. Assoon as the impellers 28, 29 which subtend the intake ports 31, 31 havereached their maximum degree of volumetric expansion, the intake valves33 close and the rotating impellers 28, 29 begin to move so as todecrease the space between them. Any gas in the chamber defined by theimpellers 28, 29 is compressed. When the impellers 28, 29 reach thedischarge ports, the discharge valves 34, 34 which have remained closedin timed relation to the impellers, are opened as the impellers 28, 29approach the point of maximum compression. That is to say, when thechamber defined between the impellers has attained its smallest cubiccapacity, the exhaust valves 34, 34 open, and the gaseous material, nowcompressed, escapes through the discharge ports 32. It will be seen thatthe compression cycles and the intake cycles proceed in pairs, inchambers from each other.

The first drive shaft 24 is supported at both ends by the bearings 23mounted on the housing. A large gear 45 is mounted on the first driveshaft 24 and another large gear 44 is mounted on the inner drive shaft25. Immediately adjacent to the inner and outer drive shafts 25, 24 is apair of coaxial auxiliary drive shafts 35, 36. Each of these driveshafts 35, 36 is supported bycentral bearings 37 and by a bearing 38 attheir outer ends.

An elliptical gear 39 is mounted on the outer auxiliary drive shaft 35and engaged with a corresponding elliptical gear 46] on a motor shaft41. Each of the auxiliary drive'shafts 35, 36 has a regular gear 42, 43mounted thereon and these gears engage the gears 44, 45 mounted on theinner or second shaft 25 and on the tubular shaft 24. The diameter ofthe gears 42, 43 is one-half the diameter of the gears 44, 45, in orderthat each chamber shall twice expand and twice contract during each 360rotation whereby there shall be two exhaust phases for each chamberduring each 360 cycle. A regular gear 46 is mounted on the motor shaft41 and this gear 46 engages the gear 43 on the shaft 36. The shaft 25 iscaused to rotate at alternately faster and slower rates of speed byreason of the elliptical gears 39, 40. Thus, the impellers 28, 29 aredriven at alternately slower and faster rates of speed with respect toeach other and vary the cubic capacity of the chambers defined betweenthem 3 in timed relation to the opening and closing of the intake 33, 33and exhaust valves 34, 34. The motor shaft 41 is driven by a motor (notshown) and is supported by the bearings 44, 44.

The operation of my compressor is illustrated in FIG- URE 3. In diagram1, chambers 1 and 3 are in exhaust phase and chambers 2 and 4 are inintake phase. Impellers A and B will be observed to define the chambers1 and 3, having small cubic capacity, and discharging the gaseous matterto be compressed. In diagram 2, impeller A has moved, but impeller B hasmoved considerably more, so that the chambers 2 and 4 are decreasing incubic capacity; simultaneously, the exhaust valves (not shown in theseviews) at the entrance to the exhaust ports xx have closed and thegaseous material is being compressed in the chambers 2, 4. In diagram 3,impeller A has moved toward the intake ports yy and the chambers 2 and 4have nearly reached their minimum cubic capacity. In diagram 4, chambers2 and 4 have nearly reached the exhaust ports x-x, the exhaust valveshave opened, the impeller B has reached its point of maximumdeceleration with respect to A, and is just beginning to increase itsspeed. The maximum degree of compression has been attained and thecompressed gaseous material is being vented through the exhaust portsx-x. In FIGURES 5, 6, 7 and 8, the chambers '1 and 3 are in compressionphase as described above for chambers 2 and 4. It is noted that witheach pair of chambers taking in gaseous material, a corresponding pairof chambers is exhausting material. Views 9 to 16 need not be explainedin detail for they merely show the chambers 1 and 3 completing theremainder of the 360 cycle, going once more through intake to exhaustphase.

An illustration of volume and pressure capacity for a set of probablevane characteristics assuming elliptic gears for two compression phasesfor each cycle or shaft revolution:

Assume:

Vane dwell=l2 Vane lead=12 Vane length=L=8" Vane width=R=4 radius ofcompressor cylinder (4 compression cycles) (qrR L) 462 in. Pressure out-905 p.s.1.) -20 p.s.1.

The major features of the compressor have been described. The secondaryfeatures of the compressor will now be described.

The housing is provided with 4 elongated shells 47 defining tripleintake and exhaust passages. Each of the triple intake and exhaustpassages 47 is divided into three sections by a pair of central fins 48terminating at the segment of an arc which is a portion of the circledefining the external surface of the housing 21 as shown in FIGURE 13.The housing is provided with triple ports 31 as shown in FIGURE 8,coincident with the triple intake and exhaust passages 47. It ispreferred that the impellers be sufiiciently thick as to covercompletely each of the ports or slots 31. A rotatable plug or valve 33closes the end of each passage. The end of each triple passage 47 isprovided with a semi-circular valve slot 49 (see FIGURE 12). The valve33 (see FIGURES 9 and 10) is pivotally mounted on an axle 50 and has apair of semicircular discs 51 mounted on a closure plate 52. The plate52 has the axle 50 for rotation. The semicircular 51 discs intimatelyengage the semicircular valve seats 49 in the passages 47. A spiralspring 53 is connected with each of the valve axles to normally urge thevalves closed.

The other end of each valve axle has a finger 54 engaged with the end ofa push-rod 55. The push-rod passes through a sleeve 56 and is providedwith a camrider 57 or head on the opposite end. A spring 58 is carriedby the push rod and inwardly urges the head into engagement with arotary cam 59. The rotary cam is mounted for rotation with the impellershaft 25. The cam is provided with four cam surfaces 60. Each camsurface 60 has a gradual slope terminating in an abrupt fall ofi or dropso that each valve is gradually moved, and abruptly restored to itsoriginal position as the riders 57 ride up and off the cam surfaces 60when the rotary cam 59 turns with the shaft 25. Thus the intake andexhaust valves are operated in timed relation to the compression anddecompression phases of the impellers.

The foregoing description is merely intended to illustrate an embodimentof the invention. The component parts have been shown and described.They each may have substitutes which may perform a substantially similarfunction; such substitutes may be known as proper substitutes for thesaid components and may have actually been known or invented before thepresent invention; these substitutes are contemplated as being withinthe scope of the appended claims, although they are not specificallycatalogued herein.

What is claimed is:

1. A compressor comprising,

(a) a generally cylindrical housing closed at each end defining anoperating chamber, the housing having intake and exhaust portscommunicating with the chamber,

(b) a tubular outer shaft rotatably mounted in the housing extendingcoaxially through the chamber, the outer shaft having diametricallyopposed, out wardly flaring radical slots,

(c) a pair of impellers mounted on the outer shaft within the chamber,

(d) an inner shaft mounted within the outer shaft and rotatableindependently on the outer shaft, a portion of the inner shaft extendingbeyond the end of the outer shaft externally to the chamber,

(e) a pair of impellers mounted on the inner shaft within the chamberextending through the slots in the outer shaft, the slots being widerthan the impellers extending therethrough,

(f) valves in each of the intake and exhaust ports,

(g) means engaged to the inner and outer shafts adapted to drive oneshaft alternately faster and slower than the other shaft, whereby theimpellers on one shaft periodically converge and diverge with respect tothe impellers on the other shaft thereby periodically increasing anddecreasing the volume of the space between the impellers and thehousing, and

(h) means engaged to one shaft and operatively connected to each of thevalves in the intake and exhaust ports adapted to periodically open andclose said valves in timed relation to the volumetric expansion andcontraction of the space between the impellers and the housing.

2. A compressor comprising,

(a) the structure in accordance with claim 1 in which the impellersextend toward close contact with the inside of the housing.

3. A compressor comprising,

(a) the structure in accordance with claim 1, and

(b) a cylindrical gear mounted on the end of the outer shaft externallyto the chamber,

(0) a cylindrical gear mounted on the end of the inner shaft externallyto the chamber,

(d) a first and second independently rotatable idler shaft,

(e) a cylindrical gear and an eliptical gear mounted on the first idlershaft, the cylindrical gear being engaged to the cylindrical gear on theinner shaft,

(1'') a cylindrical gear mounted on the second idler shaft engaged tothe cylindrical gear on the outer shaft,

(g) a third rotatable shaft,

(h) an eliptical gear on the third shaft engaged to the eliptical gearon the first idler shaft, and

(i) a cylindrical gear on the third shaft engaged to the cylindricalgear on the second idler shaft.

4. A compressor comprising,

(a) the structure in accordance with claim 1 in which (b) the housinghas a plurality of longitudinal slots communicating with the operatingchamber, each slot being parallel to the end of the respectiveimpellers, and defining intake and exhaust ports, and

(0) each impeller is wider than each of said slots in the housing.

5. A compressor comprising,

(a) the structure in accordance with claim 1 in which (b) the housinghas a plurality of longitudinal slots communicating with the operatingchamber, each slot being parallel to the end of the respectiveimpellers, and defining intake and exhaust ports,

(c) each intake and exhaust port having a plurality of slots in thehousing, each slot being narrower than the ends of the respectiveimpellers,

(d) a conduit mounted on the housing over and communicating with eachintake and exhaust port,

(e) a plurality of internal longitudinal dividing walls in each conduitdefining passages parallel to and communicating with the respectiveslots, and

(f) said valves comprising a valve in the end of each conduitoperatively connected to said means engaged to one of the rotatingshafts for periodically opening and closing the valves in timed relationto the volumetric expansion and contraction of the space between theimpellers and the housing.

References Cited in the file of this patent UNITED STATES PATENTS 88,215Ruggles Mar. 23, 1869 719,969 Wood Feb. 3, 1903 726,353 Sainsevain Apr.28, 1903 967,097 Woodward Aug. 9, 1910 1,370,548 Neebe Mar. 8, 19212,108,385 Murakami Feb. 15, 1938

